Seal for a dock leveler lip hinge

ABSTRACT

A dock leveler comprising a vehicle-engaging lip pivotally coupled to the vertically adjustable front edge of a deck includes a seal or series of seal segments that close one or more air gaps that exist in the area where the lip is hinged to the deck. Such gaps are particularly large when the lip hinge comprises a hinge pin that couples a series of lugs extending from underneath the deck to a series of lugs extending from the lip, wherein the lugs are spaced apart along the length of the hinge pin. The seal or seal segments could be above the deck, below the deck, or interposed between the adjoining edges of the deck and the lip. In some cases, the seal is provided by an air curtain or by a tube that is inflatable or hermetically sealed.

FIELD OF THE DISCLOSURE

The subject disclosure generally pertains to the lip hinge of a dockleveler and, more specifically, to a seal for such a hinge.

BACKGROUND OF RELATED ART

A typical loading dock of a building includes an exterior door with anelevated platform for loading and unloading cargo from vehicles, such astrucks and trailers. Many loading docks include a dock lever thatenables personnel and material handling equipment to readily move on andoff the vehicle bed during loading and unloading operations.

A typical dock leveler includes a deck that is pivotally hinged alongits back edge (or is otherwise mounted for vertical movement) so thatthe elevation of the deck's front edge can be adjusted to generallymatch the elevation of vehicle's bed. An extension plate or lip extendsoutward from the deck's front edge so that the lip can span the gapbetween the rear edge of the vehicle and the front edge of the deck,thereby creating a bridge between the deck and the vehicle's bed. A liphinge pivotally coupling the lip to the deck allows the lip to pivotbetween an extended operative position (where the lip is resting uponthe bed of the vehicle) and a pendant position for when the dock leveleris not in use or during certain types of loading and unloadingoperations. Some known deck and lip hinge form a significant gap and/ora series of gaps between the front edge of the deck and the lip when thelip is stored in a pendant position. Such a gap or series of gaps canintroduce outdoor air into the pit area directly underneath the deck.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic side view of a prior art dock leveler at a loadingdock.

FIG. 2 is a perspective view of a prior art dock leveler.

FIG. 3 is a cross-sectional view similar to FIG. 4 but showing a lip ofthe dock leveler in an extended position.

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 2.

FIG. 5 is a cross-sectional view of a dock leveler with its lipextended, wherein the dock leveler includes an example seal as disclosedherein.

FIG. 6 is a cross-sectional view similar to FIG. 5 but with the lip in apendant position.

FIG. 7 and 8 are views similar to FIGS. 5 and 6 respectivelyillustrating an alternative example seal as disclosed herein.

FIG. 9 and 10 are views similar to FIGS. 5 and 6 respectively butillustrating yet another alternative example seal as disclosed herein.

FIGS. 11 and 12 are views similar to FIG. 5 and 6 respectively butillustrating yet another alternative example seal as disclosed herein.

FIG. 13 and 14 are views similar to FIG. 5 and 6 respectively butillustrating yet another alternative example seal as disclosed herein.

FIG. 15 and 16 are views similar to FIG. 5 and 6 respectively butshowing an example seal suspended by an overhead door.

FIG. 17 and 18 are views similar to FIG. 15 and 16 respectively butillustrating yet another example seal suspended by an overhead door.

FIGS. 19 and 20 are views similar to FIGS. 5 and 6 respectively butshowing an example seal that can be removed completely from the dockleveler.

FIGS. 21 and 22 are views similar to FIGS. 5 and 6 respectively butshowing an example seal that overlays the deck and lip of a dockleveler.

FIGS. 23 and 24 are views similar to FIGS. 5 and 6 respectively butshowing an example seal that is to be pinched between the deck and lipof a dock leveler.

FIGS. 25 and 26 are views similar to FIGS. 5 and 6 respectively butshowing an example seal that can be inflated or hermetically sealed.

FIGS. 27 and 28 are views similar to FIGS. 5 and 6 respectively butshowing an example forced current of air that determines the directionof airflow through the gap of a lip hinge.

FIGS. 29 and 30 are views similar to FIGS. 5 and 6 respectively butshowing an example seal in proximity with the lip hinge pin of a dockleveler.

DESCRIPTION OF THE PREFERRED EXAMPLES

FIGS. 1-4 illustrate a conventional dock leveler 10 installed at aloading dock 12 to facilitate the loading and unloading of a vehicle 14at a vertically movable door 16. Dock leveler 10 comprises a deck 18, alip 20, and a lip hinge 22. A rear deck hinge 24, or some other means,renders a front edge 26 of deck 18 vertically movable to accommodate anindeterminate bed height of vehicle 14. Lip hinge 22 pivotally coupleslip 20 to deck 18 so that lip 20 can pivot between a pendant position(FIG. 4) and an extended operative position (FIG. 3). In the extendedposition, lip 20 can rest upon the bed of vehicle 14 to create amaterial handling bridge between vehicle 14 and a platform 28 of dock12. Lip 20 can be moved to the pendant position for storage or forcertain vehicle servicing operations.

Lip hinge 22 of dock leveler 10 comprises a plurality of deck lugs 30extending from underneath deck 18 and a plurality of lip lugs 32extending from lip 20. Lugs 30 and/or 32 can be welded or otherwiseattached to their respective structure from which they extend. A hingepin 34 couples lugs 30 to lugs 32 so that lip 20 can pivot relative todeck 18.

When the dock leveler 10 is not in use, the deck is typically storedhorizontally with the lip 20 in the pendent position. In this position,a significant air gap 36 and/or series of air gaps exist between lip 20and deck 18. In particular, the gap 36 and/or series of gaps are createdby the spaced-apart hinge lugs 30 and 32 and allow outdoor air to flowto an area underneath the deck 18. If gap 36 is left exposed orunsealed, indoor or outdoor air can leak through gap 36. Such a gap 36or series of gaps that are unsealed or exposed can introduce outdoor airinto a pit area directly underneath the deck 18. If the outdoor air issufficiently cold, condensation and frost might accumulate on the uppertraffic surface of the deck 18, as the deck 18 is typically thermallyconductive and exposed to relatively warm indoor air. If the outdoor airis warmer than the indoor air, moisture might condense on the undersideof the deck, which can lead to corrosion of the dock leveler's 18components.

In the following, various example methods and apparatus are disclosed toprovide a mechanical and/or fluid dynamic seal that substantiallyprevents or obstructs or, at least controls, the airflow through gap 36.

An example seal 38 illustrated in FIGS. 5 and 6, for instance, includesone or more resiliently flexible members that span gap 36. A pluralityof seals 38 are installed to cover a series of gaps 36 created byaxially spaced apart lugs 30 and/or 32. Seal 38 can be of anyappropriate shape, size, and/or material including, but not limited to,a piece of resiliently flexible material (e.g., sheet metal); a brush;or a sheet, pad or block of foam, plastic or rubber. One end 40 of seal38 can be attached to deck 18 by way of any suitable fastener 42including, but not limited to, a screw, adhesive, weld bead, etc. Anopposite end 44 of seal 38 can slidingly seals against the underside oflip 20 as lip 20 pivots between the extended position (FIG. 5) and thependant position (FIG. 6).

Alternatively, as illustrated in FIGS. 7 and 8, end 40 of seal 38 can beattached to lip 20 while end 44 slidingly seals against the underside ofdeck 18.

In other example implementations, a seal, similar to seal 38, may beimplemented with a mounting structure or fastener. For example, asillustrated in FIGS. 9 and 10, a flexible seal 46 includes a mountingstructure or fastener (illustratively, in the form of a clip 48) thatattaches to hinge pin 34 so that both ends 50 and 52 of seal 46 canslidingly seal against their respective sealing surfaces of deck 18 andlip 20.

In another example, as illustrated in FIGS. 11 and 12, a seal 54 isprovided which includes an alternate mounting structure to clip 48. Inthis example, the seal 54 comprises one or more resiliently flexibleends 56 and/or 58 that can slidingly seal against respective sealingsurfaces of deck 18 or lip 20. End 56 of seal 54, for example, cancomprise a polyethylene sheet of material 60 sewn within a fabric cover62 that wraps around hinge pin 34. A hook-and-loop fastener 64 can helphold seal 54 to hinge pin 34. End 58 of seal 54 can be an extension offabric cover 62.

In another example shown in FIGS. 13 and 14, one or more seals 66comprise a tubular piece or structure. The tubular piece may be made ofpolyurethane foam, similar to that commonly used for insulating pipes,or any other suitable insulating material(s). In some exampleimplementations, seal 66 is implemented by a series of relatively shortsegments distributed axially along hinge pin 34 to cover or fill gap(s)36 that might otherwise exist between lugs 30 and/or 32. Seal 66preferably has an outer perimeter that can press radially outwardagainst deck 18 and lip 20. In other example implementations, seal 66includes a joint 68 that is held together by adhesive or by any othersuitable fastening mechanism(s). In yet other example implementations,seal 66 is a jointless tube that is installed at the same time hinge pin34 is inserted through lugs 30 and 32.

In yet another example shown in FIGS. 15 and 16, a seal 70 comprises aflexible fabric or sheet of material suspended from door 16 such thatseal 70 overlays gap 36 when door 16 is in a closed position (FIG. 16).As illustrated in FIGS. 17 and 18, a seal 72 similar to seal 70 of FIGS.15 and 16 is made of sheet metal, as shown in FIGS. 17 and 18.

Referring to FIGS. 19 and 20, another alternative example seal 74 ismade of a sheet of material removably held in place by one or moremagnets 76. In this example, seal 74 is removed when the dock leveler 10is in use. When the dock leveler 10 is inactive or stored, seal 74 canbe laid over gap 36, as shown in FIG. 20.

FIGS. 21 and 22 show a seal 78 that is similar to seal 38 of FIGS. 5 and6, but installed on top of deck 18 and lip 20. In this example, seal 78is resiliently flexible and has a relaxed shaped as shown in FIG. 22.The flexibility of seal 78 enables seal 78 to flex from its shape ofFIG. 22 to that of FIG. 21. Either end of seal 78 can be attached to lip20 (as shown) and/or attached to deck 18. This configuration isparticularly advantageous because installing the seal 78 atop of deck 18and lip 20 enables seal 78 to be made as a substantially unitarystructure (e.g., a single, full-length piece extending the width of thedeck) rather than having to make seal 78 as a plurality of segments thatcover and/or fit within the gaps between lugs 30 and 32. Seal 78 can bemade of any suitable material including, but not limited to, plastic orrubber.

In another example shown in FIGS. 23 and 24, a seal 80 includes aserpentine or accordion-type sheet that can be made of plastic, metal,or any other suitable material(s) that can flex and/or fold. When lip 20is in the pendant position as shown in FIG. 24, seal 80 can expand tocover any gap that might otherwise exist between lip 20 and deck 18.When lip 20 is in the extended position as shown in FIG. 23, seal 80collapses upon being pinched between lip 20 and deck 18.

In yet another example shown in FIGS. 25 and 26, a seal 82 comprises aseries of gas-filled flexible tubes 84 that are distributed along thelength of hinge pin 34 to help fill the air gaps between lugs 30 and/or32. A hollow chamber 86 within each tube 84 can be permanently chargedwith a fixed amount gas and hermetically sealed and/or a common manifold88 can connect tubes 84 to the discharge of a blower 90 that delivers asupply of pressurized air into the tubes.

FIGS. 27 and 28 illustrate a method of substantially inhibiting outdoorair 92 from flowing into the building through gap 36. Blower 90 draws inoutdoor air 92 and discharges it through a manifold 94 that includes aplurality of nozzles 96 aimed at gap 36. Nozzles 96 discharge thedrawn-in outdoor air 92 upward and outward toward and/or through gap 36,thereby creating an outward flowing current of air 98 that inhibitsoutdoor air 92 from flowing in the opposite direction of air 98 throughgap 36.

FIGS. 29 and 30 illustrate a plurality of example seals 100, each ofwhich includes one end 102 attached to the underside of deck 18 or lip20. An opposite end 104 of each seal 100 slidingly engages and/or is atleast sufficiently close to shaft 34 to provide a substantialobstruction to substantially prevent the ingress of air attempting topass through gap 36. In the illustrated example, seals 100 aredistributed along the length of hinge pin 34 to fill the plurality ofgaps created by the axially spaced apart lugs 30 and/or 32. In theillustrated example, seal 100 is preferably made of a resilientlyflexible metal or polymeric material. However, in other exampleimplementations, seal 100 can be made of a rigid material (e.g.,plastic), particularly if seal 100 is positioned in close proximity toshaft 34 and does not engage and/or slide against shaft 34.

From the foregoing, it will be appreciates that example methods andapparatus have been disclosed whereby an air gap between the deck andlip of a dock leveler is at least partially blocked by a seal thatextends from the lip to the deck in the vicinity of a hinge thatpivotally couples the lip to the deck.

In some examples, a seal for a dock leveler's lip hinge is installedbeneath the deck and the lip.

In some examples, the seal is disposed generally above the deck, lip andlip hinge.

In some examples, a seal for a dock leveler's lip hinge includes someseal segments that extend from the lip to the hinge pin and other sealsegments that extend from the deck to the hinge pin.

In some examples, a seal is attached to the lip and slidingly engagesthe deck, and in other examples, the seal is attached to the deck andslides against the lip.

In some examples, the gap between a lip and a deck is sealed by a sealmember that is attached to a hinge pin.

In some examples, the gap between a lip and a deck is sealed by atubular seal member made of resiliently compressible foam.

In some examples, the gap between a lip and a deck is sealed by atubular seal member that is inflated by a blower or is hermeticallysealed with a fixed charge of gas.

In some examples, the gap between the lip and deck of a dock leveler issealed by a seal member that is carried by a vertically operating doorthat is adjacent to the dock leveler.

In some examples, the gap between a lip and a deck is sealed by aremovable seal member that can be held in place by a magnet.

In some examples, an inward flow of air through the gap between a lipand a deck of a dock leveler is inhibited by blowing a current of airoutward through the gap.

Although certain example methods, apparatus and articles of manufacturehave been described herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe appended claims either literally or under the doctrine ofequivalents.

1. A seal for a dock leveler that includes a pivotal lip hinged to avertically movable deck, wherein the deck and the lip define a gaptherebetween, the seal comprising: a flexible member spanning the gap.2. A dock leveler, comprising: a deck that is vertically movable; a liphinged to the deck such that the lip, relative to the deck, is pivotalbetween a pendant position and an extended position, the lip and thedeck define a gap therebetween when the lip is in the pendant position;and a flexible seal spanning the gap.
 3. The dock leveler of claim 2,wherein the flexible seal is underneath the deck and the lip when thelip is in the extended position.
 4. The dock leveler of claim 2, whereinthe flexible seal slidingly engages at least one of the deck and thelip.
 5. The dock leveler of claim 2, further comprising a hinge pin thatpivotally couples the lip to the deck, wherein the flexible seal isattached to the hinge pin.
 6. The dock leveler of claim 5, furthercomprising a hook-and-loop fastener attached to the flexible seal,wherein the hook-and-loop fastener couples the flexible seal to thehinge pin.
 7. The dock leveler of claim 5, further comprising a clipattached to the flexible seal, wherein the clip helps fasten theflexible seal to the hinge pin.
 8. The dock leveler of claim 2, furthercomprising: a plurality of deck lugs extending outwardly from underneaththe deck; a plurality of lip lugs extending from the lip; and a hingepin coupling the plurality of deck lugs to the plurality of lip lugs,thereby pivotally coupling the lip to the deck.
 9. The dock leveler ofclaim 8, wherein the plurality of deck lugs and the plurality of liplugs define a plurality of gaps distributed along a length of the hingepin; and further comprising a plurality of seals disposed within theplurality of gaps, wherein the flexible seal is one of the plurality ofseals.
 10. The dock leveler of claim 2, wherein the flexible seal istubular.
 11. The dock leveler of claim 2, wherein the flexible sealcomprises a resiliently compressible foam material.
 12. The dock levelerof claim 2, wherein the flexible seal comprises a fabric material. 13.The dock leveler of claim 2, wherein the flexible seal comprises aresiliently flexible sheet metal.
 14. The dock leveler of claim 2,wherein the flexible seal extends from a door that is above the deck.15. The dock leveler of claim 2, wherein the flexible seal is above thedeck and the lip when the lip is in the extended position.
 16. The dockleveler of claim 2, further comprising a magnet that attaches theflexible seal to at least one of the deck and the lip.
 17. The dockleveler of claim 2, wherein the flexible seal is positioned to bepinched between the deck and the lip when the lip is in the extendedposition.
 18. The dock leveler of claim 2, wherein the flexible sealcomprises an inflatable tube.
 19. The dock leveler of claim 2, whereinthe flexible seal defines a hollow chamber that is substantiallyhermetically sealed.
 20. A dock leveler, comprising: a deck that isvertically movable; a lip that relative to the deck is pivotal between apendant position and an extended position; a hinge pin that pivotallycouples the lip to the deck; and a plurality of seals each of whichinclude one end that is attached to at least one of the deck and the lipand an opposite end that is adjacent to the hinge pin.
 21. The dockleveler of claim 20, wherein the opposite end slidingly engages thehinge pin.
 22. The dock leveler of claim 20, wherein at least one sealof the plurality of seals is attached to the deck, and at least a secondseal of the plurality of seals is attached to the lip.
 23. A method ofproviding a weather resistant dock leveler that includes a pivotal liphinged to a vertically movable deck, wherein the deck and the lip definea gap therebetween, the method comprising: drawing in a current ofoutdoor air; and forcing the drawn-in outdoor air upward and outwardthrough the gap, thereby substantially inhibiting other outdoor air frompassing through the gap.